Once you get to the "New in Splunk Enterprise" pop-up and learn about the Datasets Add-on, clicking the "Get the Datasets Add-on" button yields this error:
404 Not Found
Return to Splunk home page
Page not found!
View more information about your request (request ID = 5887714bc27faf006a1c10) in Search
This page was linked to from http : //:8000/en-US/app/search/datasets.
You are logged into :8000 as admin, which is connected to splunkd @f74036626f0c at https : //127.0.0.1:8089 on Tue Jan 24 10:22:51 2017.
The button links to: http://:8000/en-US/app/search/undefined
If I then click on "View more information about your request (request ID = 5887714bc27faf006a1c10) in Search", I get "No results found." for the search "index=_internal host="sds-dut-vb" source=*web_service.log log_level=ERROR requestid=5887714bc27faf006a1c10", which is not helpful.
I'm one of the engineers who worked on the Splunk Datasets Add-on. Thanks for your report. By any chance, were you on some sort of intranet when you clicked that link, or otherwise didn't have internet access? Looking at the code now, if for some reason there was a problem connecting to splunkbase.splunk.com, then you'd experience what you described. This is an oversight on my part! I've filed a bug and we'll address it very soon. Thanks for bringing it to our attention!